Sedentary behavior and physiological health determinants in male and female college students

Background: Sedentary behaviors are associated with numerous adverse physiological health outcomes, morbidity and mortality, although with limited knowledge in young adults. Aim: To assess the association between sedentary behavior, muscular strength and body composition in male and female young adult college students. Methods: A cross-sectional pilot study was conducted among 94 college students (20.2 +/- 1.6 years, 46 males and 48 females) from a University in the Mid-Atlantic region, US. Students were assessed for sedentary behavior, physical activity and objective physiological variables including lean body mass (LBM), fat% and muscular strength [1-Repetition Maximum (1-RM)]. Descriptive statistics and linear regression analysis were conducted. Results: Sedentary behavior (sitting time >= 6 h/day) was prevalent in 69% of females and in 46% of males, p = .036, although most students (84-94%) met the physical activity recommendations. Sitting time inversely correlated with LBM (r = -0.58, p = .01) and trending for positive correlation with fat% in females, whereas in males, sitting time inversely correlated with 1-RM upper body strength (r = -0.46, p = .017). Female students who sat >= 7.5 h/day had approximately 10-fold increased chance of being obese [odds ratio = 9.6, 95% confidence interval (1.5 to 62.7), p = .019] compared to non-sedentary. Conclusions: Although most students were physically active, considerable prevalence of sedentary behavior was observed. The novel findings showed that, sedentary behavior was associated with compromised physiological health determinants of body composition in females and muscular strength in males. Reducing sedentary behavior among active college students could be a public health strategy for health promotion and chronic disease prevention.